drm/exynos: change callback argument of sub driver with device

[Dave Airlie]

>
>> to DT nodes, but it isn't essential. So I'd like to move away from the
>> 1:1 DT node/driver
>> model as it seriously over complicates things. We have agreed we
>> should possibly add
>> a display virtual node in the DT bindings for a single driver to use
>> as a binding point.
>
> Got it and thanks you for comments. The display virtual node seems
> similar to super node posted by Russell King so just my concern is
> that the display virtual node can be accepted by device tree people.
> Anyway, I'll remove this patch. I really wish that the display virtual
> node can lead us to more perfect world.

Just to confirm, Grant Likely was in the room for the discussion was
quite happy to add them.

Dave.